Maghemite

MAGHEMITE (from magnetite and hematite), a mineral, a magnetic modification of iron oxide e-Fe2O3- Usually contains FeO and TiO2 impurities. Unstable in natural conditions and easily transforms into stable hematite. It crystallizes in a square system (pseudocubic), having a defective spinel structure of the magnetite type. TV. on mineralogical. scale 5-6; density 4700- 4900 kg/m3. Color dark brown with a steel sheen; opaque. In nature, it occurs only in the form of microscopically small secretions in the oxidation products of magnetite, in titanomagnetites together with hematite, iron hydroxides, etc.; less often - in brown ironstones and laterites as a product of surface weathering of ferrous minerals.